Stapling machine



Nov. 4, 1930. A. H. MAYNARD STAPLING MACHINE Filed Dec; 21, 1927 3 Sheets-Sheet l Nov. 4, 1930.

A. H. MAYNARD STAPLING MACHINE 5 SheetS-Sheet 2 Filed Dec.

NOV. 4, 1930. v MAYNARD 1,780,530

STAPLING MACHINE Filed Dec. 21, 1927 3 Sheets-Sheet, 5

I Patented Nov. 4, 1930 4 I UNITED STATES PATENT" OFFICE Amazon 11-. MAYNARD, or wAnwxcx, nnom: IsLAND, ASSIGNOR 'ro nosroN WIRE srxrcnnn COMPANY, or PORTLAND; MAINE, A CORPORATION or MAINE STAPLING MACHINE Application filed December 21,1927. Serial No. 241,591.

This invention relates to stapling, and

' 6 jects, and for use generally for stapling or" stitching together any parts or articles.

A principal object of the present invention is to rovide an eflicient device ofthe type speci ed which is simple in its mechanical construction, compact in size and economical to manufacture. V

Another object of the invention is to pro vide a device of the type specified in which the staples are automatically fed to the stapling mechanism, for example the reciprocating staple-driver, and in which the feeding of the staples is so controlled that the first staple must be driven completely into the work beforea second staple is fed to the driver, whereby to prevent clogging of the machine or the application of one staple on top of another, p s H v Another object of the inventionis to provide" means for insuring that every staple is prolperly directed'to and driven into the work wit ut danger'of its being bent .or malformed previous'to; or during the operation o'fsetting thestaples in the work,

, Another object .of the invention is to pro f '3 vide a simplified means for operating the clincher-devices which bend over the legs of, the staple and clinch them against the under;

side of the work.

Further objects of the improvement are set forth in the following specification which describes a preferred form of construction.

-'of theinvention as illustrated by the accompanying drawings. In the drawingsi Fig."1-is a' side view of a hand-operated stapling, machine embodying the invention; Fig. 2 is a side elevation of the machine in opposite View, sho'winglit partly in "section to illustrate certain details of the operating mechanism; and re' resenting it at} the start of? the foperationo applying a staple to -"the' work; v

.' Fig. I 3 *is an. elevation of the forward end of the stapling machine illustrating it with' the stapling mechanism raised and out ofoperation; M

r The invention is herein described and il- Fig. 4-is a similar view showing the staplingmechanism lowered against the work with its parts in position at the completion of the stapling operation; v i

Fig. 5 is a sectional View of the stapling mechanism taken on line 55 of Fig. 3 with the parts shown in position at the beginning of the stapling operation;

Fig. 6 is a similar sectional View taken on line 66 of Fig. 4 and showing the stapling mechanism with its parts in position at the finish of the stapling operation; 7 I

Fig. 7 is a cross-sectional view of the stapling-head of the machine taken on line 77 0fFig.1;' w

Fig. 8 is apart sectional plan View of the forward portion of the base of the machine showing the clincher-devices in place thereon; v J

Fig. 9 is an enlargedside View partly in section of the lower portion of the staplinghead of the machine; and v Fig. ,10-is an enlarged plan view'in'section of this portion ofthe machine taken on line 1010 of Fig. 9. w

lustrated as embodied in a stapling machine of the hand-operatedtype, but it is to be understood that certain or all of its features may be applied to use with machines'of other, types, for example, on power-operated. stitching or stapling machines. I,

In general, the improved machine comprises a :base, or support, a -'st'apling1arm hinged theretoand constituting a magazine 35 for holdinga supplfy of staples, means for I feeding the staples rom the=magazine,1an d-" ea stapling-head. 'at-theforward 'endof the arm )carrying means for operatingupon the individual staples as they-are delivered there to todrive them into or throughthework. "Preferably, the improved machine also im eludes clinchersdevices on the' base which are controlled from the stapling mechanisming, the head to bend over and clinch ,ithe legs of the staple against the underside .Qflthflli'i work through which they are idrive'ni izThe base of the-machine andtheclincher-devices may be dispensed with, however,' and ,the

, present improved stapling-head be employed proved machine is constructed largely of sheet-metal parts which may be stamped out and formed in suitable dies to render the structure economical to manufacture. In the drawings, 2 designates the longitudinal support or base of the machine, 3 indicates the hinged stapling-arm which serves as a magazine for the supply of staples, and 4 is the ;tapling-head containingthe mechanism for driving the staples into or through the work and which may be operated by a sliding plunger 5.

The base 2 of the machine is preferably constructed from sheet-metal struckup in channel form and positioned as an inverted trough. -As herein shown the base 2 is constituted by flat side-strips 9 bent down from a top-strip 10 and having wings or lateral flanges 11 bent outwardly at the bottom and adapted to rest on heavier'cross-strips 12 at the forward and rearward ends thereof to provide feet on which the machine stands. The feet or rests 12 may be riveted or welded to the side-flanges 11 and it will be understood that the under side of the base 2 is open along its length between the two end-rests. A separate strip or plate 15 extends along the under side of the base 2, being supported at its ends by the rests 12 and adapted to slide thereon between the sides t) of the base.

The slide 15 constitutes the means for controlling the clincher-devices at the forward end of the base 2 through connections to be later described. Suflice it for the present to state that the slide 15 is held in place by inner side-plates 16 abutting the interior of the sides 9 of the base 2 and welded or otherwise suitably fastened thereto with their lower edges overhanging the marginal edges of the slide, see Figs. 2 and 8. Referring to this latter view, the forward ends of the side-plates 9 of the base 2 are bent inwardly to form flanges'or walls 17, see also Fig. 3, between whichand similar bent flanges 27 on the inner plates 16 areslidably held the clinchercarrying plates 18. -Referringparticularly to Figs. 2, 3, 4 and 8, the clincher-plates 18, which are of rectangular outline, arev held in parallel spaced relation by means of pins-19 and spacer washers 20, see Fig. 4. The two.

plates are not riveted together, however, but may be taken apart for a purpose as later ex plained. Pivoted between the plates 18 arethe clinchers 22 carried on pins 21.

The clinchers 22 are of the usual form having their upper edges recessed slightly to receive the ends of the legs of the staples which are forced upwardly thereby .to clinch them in place with their points penetrating into the under side of the work in the manner as later 'more fully explained. The lower edges of the clinchers 22 bear against the crowned upper face of a vertical member or rest 23 which is held between the two clincher-plates 18 with its sides bearing against the rims of the spacer washers 20. The clincher-rest 23 has a vertical slot at its center through which ex tends a stud 24 arranged with its central portion engaging the sides of its slot and its reduced ends projecting through holes in the clincher-plates 18. The clincher-rest 23 has its lower edge resting on the cross-strip or foot 12 at the end of the base 2 and it is .to be noted that the two ends of the rest are of like form so that when one end is worn by the sliding contact of the clinchers it may be taken out and reversed in position.

The clinchers 22 are operated to throw their free ends upwardly to cause them to act against the legs of the staple by sliding the clincher-plates downwardly in their guideway at the forward end of the base 2. Normally, the clincher-plates 18 are held in raised position, as illustrated in Fig. 3 of the drawings, with their lower edges resting against a step or abutment 25 at the forward end of the slide 15. As shown in Figs. 2 and 8 the step 25 consists of a flat plate welded or otherwise suitably fastened to the top of the slide 15 and extending thereacross between the side plates 9 of the base 2. At its forward end the step or plate 25 is cut away or slotted in the center to form two opposite fingers or lugs 26 which project under the lower edges of the clincher-plates 18 when the slide is in its forward position. The underlying forward end of the slide 15 is also cut away in the same manner whereby a space or slot is provided for the clincher-rest 23 which, as before explained, is supported with its lower edge resting on the top of the crossrest or foot 12, see Figs.'2 and 3. It will be understood that the work to be stapled, indicated at w in Fig. 2, rests across the upper edges of the clincher-plates 18 as the staplinghead is brought down to apply the staple. The descent of the plunger 5 to drive the staple through the work is caused to slide the clincher-plates downwardly to operate the clinchers, the step 25 beneath the clincherplates being first withdrawn by the rearward sliding motion of the slide 15. The slide 15 by the descent of the plunger 5 carrying the staple-driver. I Pivoted on a cross-pin 29 riveted through the sides of the base 2 at the rearward end is slid back under the control of instrumentalities as next described which are actuated ing end 33 which engages a slot 34 in the slide 15. One wingor side 31 of the lever 30 is extended upwardly throu h an opening in the top of the base 2 to which is pivotally connected at 36 to a bar or link 37 reaching forwardly to the staplinghead 4 on the arm 3, see Fig. 1. The lever 30 is normally maintained with its lower-end rocked forwardly by means of awire spring 38 coiled around its pivot-pin 29, one leg 39 of the spring bearin against the under side of the top-strip 10 0 the base 2 and its other leg 40 acting against the edge ofthe crossstrip 32 of the lever. The forward end of the link 37 is connected to the upright arm 41 of a lever 42 which is pivoted at 43 to the side of the stapling-head 4. The lever 42 has a forwardly extending arm-44 formed with a toe 45 which is adapted to be engaged by a lug 120 on the lower end of the plunger 5 during the descent of the latter in the manner and for the purpose as hereinafter more fully explained.

. The clincher-plates 18 are returned to raised position as illustrated in Fig.3, to allow the slide 15 to be moved forward in under their loweredges, by meansof a fiat leaf-spring 46, see Fig. 2. The spring 46 underlies the top-strip 10 of the base 2 at the forward end thereof and is secured in place by a novel construction as'next described. The top'-platee10 is slitted across its width to provide a narrow strip 13 of the metal which is punched or forced downwardly to form a loop underlying the bottom of the spring to hold it snugly against the bottom of the top-plate.

Rearwardly of the loop 13 the top-plate is punched or indented to form a rounded teat or projection 14 which engages a hole in the spring 46 to restrain the latter from longitudinal movement. The spring 46 is thus securely fastened to the under side of the top-strip 10 without the use of screws, rivets or other extraneous fasteningmeans. The free end of the spring 46 engages a slot 53 in the'rearward clincherplate 18. The forward end of the spring 46 is thus adapted to flex downwardly, as shown bythe dotted lines in Fig. 2, when the clincher-plates 18 are carried down during the operation of driving the legs of the staple through the work.

The staplin -arm 3 which carries the stapling-head 4 is preferably constructed as a,

fiat metal bar of suitable width to adapt the staples s to be straddled across its top. At its rearward end the arm 3 has fastened to its under side a rectangular block 47 held by rivets 48. This end of the arm 3 is received within the sides of a U=shaped sheet-metal cradle 49 which is welded to the top of the base 2. A pivot-pin 50, driven through the sides of the cradle 49, passes through a hole in the block 47 whereby the arm 3 is hingedly orm an arm 35- mounted to swing with respect to the base 2. At the forward end of the block 47 a hole 52 is drilled up into the arm 3 to provide a pocket for a coiled spring 54. The end of the spring 54 bears againsta plunger 55 slidable in the bore 52 and having its lower rounded end bearing against the bottom of the cradle 49. The pressure of the spring 54 thus acts through the plunger 55 to normally maintain the arm 3 in raised position, as shown in Fig. 1, with the rearward end of its block 47 bearing against the bottom of the cradle 49 to restrainthe arm from further movement.

' of the arm 3 comprises opposite vertical sideplates 57 fastened to the sides of the arm. As herein shown the plates 57 are doweled to the arm by means of pins 58 and clamped against its sides by the screws 43and 60, the former of which having been previously referred to as the pivot for the lever 42. As shown in Fig. 10, this screw 43 has an enlarged body portion arranged with its shoulder set up against the side-plate 57 and form-- ing the bearing for the lever 42. The sideplates 57 reach upwardly above the top of the arm 3 to form a hollow casing and are rounded off on their rearward edges. Abutting the inner faces of the plates 57 are thinner lining-plates 61 secured in lace by means as later described. The limng-plates 61 have their lower edges spaced slightly above the top of the arm 3 to provide a channel for the upper cross-bar of the staples 8, see Fig. 2, and it is to be noted by reference to Fig. 7

that the outer plates 57 are cut away'or slotpointed prongs 63 bent inwardly to form a '7 rest for supporting the lower end of the coiled spring 65 which acts to retract the plunger 5 in the manner as later explained.

Thelining-plates 61 are held in position abutting the inner faces of the outer plates 57 by spacer-hubs 66 and 67. The upper spacer-hub 66 has an enlarged central body portion, the shoulders of which abut the inner faces of the plate 61, and reduced ends projecting through holes in the plates. Suitable sorews 68 are screwed into threaded axialholes in the hub 66 to clamp the plates thereagainst. The second spacer hub 67 is constructed in the form of a stud having an enlarged centralportion arranged with its shoulders abutting the innerfaces of the lining-plates 61 and its reduced'ends inserted -th.rough holes in the inner plates. This stud sides straddling the top of the arm 3 as shown in Fig. 2. At its rearward end is. a tail-piece 71 having a hook 72 enga ed through an opening in the bottom 0 a curved finger-loop 73. The forward end of the finger-loop 73 is slittedto adapt it to receive the end of the flat ribbon-like spring 69, before referred to, which is bent through the slits to secure it thereto. The forward end of the spring-69 is wound into a convolute coil 74 with its inner end secured to a hollow cross-member 75 held between the side-plates 57. From the coil 74 the spring extends down under the guiding stud 67, and reaching back to the pusher 70 tends to slide the latter on the arm 3 whereby to feed the seriesof staples forward to deliver them individually under the staple-driver in the manner as later more fully explained; A staple-guard 76 constructed as a sheet-metal strip is welded to one side of the arm 3, see Fig. 1, and folded across the upper part thereof in spaced relation with respect to its top, see Fig. 2, The staples Z9 slide in the space 77 between the overhanging guard 76 and the top of the arm 3 and are thereby restrained from rising up off of the arm.

The plunger 5 which is reciprocated to operate the stapling mechanism comprises a hollow or part-tubular shell 80, see Figs. 1, 2 and 7, which may be struck up from sheet-metal. The opposite sides of the shell 80 straddle the forward (sides of the head 4 and are bent inwardly as shown in Fig. 10 to provide splines or runners 81 which slide in vertical grooves 82 formed in the outer faces of the plates 57. At the top of the plunger 5 is a knob or presser 85 havingits hub 86 fitted within the sides of the shell 80 and fastened in place by a screw 87 reaching through from the front. A pin 88 projects downwardly from the hub 86 of the knob 85 and passes through the upper coils of the spring 65 which, as before stated, has its lower end resting on the prongs 63. The spring 65, as will be observed by reference to Fig. 2, acts to raise the plunger5 to its uppermost position and to return itto this position after each strokeis made to apply a staple to the work.

The staple-driver 90 is of usual form, being constructed as a narrow blade shouldered on its lateral edges to provide narrow splines 91 which slide in vertical grooves or guideways 92 formed on the inner faces of the side-plates 57 ofv the head 4, see Fig. 10. Referring to F igs. 5*and 6, the staple-driver 90 is held in parallel spaced relation with respect to the forward wall ofsthe shell'80 by means of a shouldered stud 93. The stud93 has a reduced portion riveted throughthe front of the shell 80 and a reduced shank at rearward end projecting into a 'hole in the staple-driver 90. Preferably, the stapledriver 90 is provided with two holes so that it may be reversed in position when its lower edge becomes worn. The upper edge of the staple-driver 90 bears a ainst the under side of the hub 86 on the ob 85 to take the thrust thereof when the plunger .5 is slid downwardly during the stapling operation. It will be understood that the staple-driver 90 slides downwardly in its guideways 92 at the front of the head 4 to cause its lower edge to impinge against the top ofthe forward staple fed off from the staple-core or arm 3- as shown in Figs. 2.and 5. h

It will be observed by reference to Figs. 2, 5, 9 and 10 that the grooves 92in the sideplates 57 extend downwardity across the front of the staple-core or arm-3- so that when the leading staple in the series feeds off. from the end of the arm its legs will be held in the grooves bearing against the forward edges thereof. It is also to be noted that this forward edge of the groove in each sideplate is staked or cut away at an angle to the front end of the staple-core 3 to provide a clearance so that if one of the legs of the staple is bent out of alinement the other leg will be permitted to swing clear of the arm 3. as 'it passes out of the side channel 62 in the side-plate 57. It is to be further observed that the legs of the forward staple are held frictionally in the grooves 92 by the pressure of the following staples feeding from the rear until this forward staple is carried downwardly by the descent of the driver 90.

The under side of the forward end of the staple-core or arm 3 is cut away or recessed at 94 and as the staple being driven slides downwardly beyond the control of the following staples it engages with a supporterv 95 which prevents it from dropping out of the grooves 92. The staple-supporter 95 consists of a spade-shaped lever, shown in front view in Fig. 3, having its upper narrower arm 96 pivoted in a vertical slot 97 cut through the upper projecting end of the staple-core or arm 3. The staple-supporter 95 is pivoted on a cross-pin 98 to adapt its lower widened blade 99't o swing back into the recess 94 on the under side of the arm 3- as shown in Fig. 6, this action taking place as the staple-driver 90 slides down beyond the bottom of the stapling-arm.

Normally, when the staple-driver 90 is in raised position as shown in Fig. 5, thestaple-' supporter 95 is urged outwardly by the action of a plunger 100 which slides in a bore ,101 in the arm 3 under the force of a coiled spring 102 pocketed in the bore. The 7 by a screw'106. The outer projecting portion of the pressure-foot 105 is offset downwardly away from the bottom of the arm 3 and is cut away at 107 to enclose two opposite lugs 108 on the sidepl'ates 57 which reach downwardly beyond the bottom of the arm. The forward part 109 of the pressere foot 105 is adapted to bear against the work w laid across the edges of the clincherplates 18 in the manner as illustrated in igs. 4, 5 and 6.

It will be understood that the knob or presser 85 is pressed downwardly, against the force of the spring 65 whereby to slide the plunger 5 downwardly to actuate the staple-driver 90; the reciprocatory action of the plunger being controlled by a novel arrangement of means which prevents .the driver from being withdrawn or raised above the sta le-core or arm 3 unless or until the staple being acted upon has been driven completely into or through the work. This improved means is shown in detail in Figs. 2 to 6 and comprises essentially. an automatically operated detent-catcher trip-latch 110 on the plunger 5. In its simplest form the latch 110 may consist of a flat strip of sheet-metal held against the front of the plunger-shell 80 with its upper hookedend 111 projecting through a lateral slot 112 therein.- A flat leaf-spring113 securedto the front of the plunger-shell 80 by the screw 87, previously referred to, reaches down to overlie the latch 110 to normally hold it flat against'the -frontof the plunger. The lower end of the latch 110 is formed with a curved or oifset cam-portion 114 terniinating'in adetent projection or catch 115. This last-described lowerbent portion 114 of the latch 110 is adaptedto enter through a relatively wide slot 116 in the wall of the plunger-shell 80 when the latch is pressed flat against the front of the plunger 5 as shown in Fig. 5. With' the plunger 5 in raised position, however, as shown inXFigs. 1, 2 and 3, the latch 110 is canted outwardly at its lowerend with its detent or catch 115 engaging a relatively shallow notch or shoulder 117 cut into the forward edges of the side-plates 57 on the head 4.. Below the shoulder 117 is a second shoulder or notch 118 with which the de tent or catch115fof the latchllO engages:

when the plunger 5 is pressed downwardly to a sufiicient extentto bring the loweredge of the staple-driver 90 across the upper edge of the staple-core or arm 3. Av third shoulder. or abutment 119 is provided on the plates 57'. adjacent the bottom of the head .4 for the purpose of engaging the catch'115 a to trip the latch 110. The manner ofengaging the latch. with the several shoulders to control the action of the plunger 5 will be more readilyunderstood from a descrip illustrated with its base 2 resting on a suitable support and the sta ling-arm 3 held raised under the action of t e spring-plunger 55. The work w, which may comprise sheets of paper, cardboard or other material to be stapled or stitched together, samples of cloth to which tags or labels are to be attached, or any other articles or objects to be fastened together, is laid across the upper edges of the clincher-plates 18 as shown in Figs; 2, 4 and 6. After the work has been placed in position in this manner the operator presses his hand againstthe knob 85 to swing the arm 3 downwardly whereby to carry the presser-foot 105 against the work as shown in Fig. 2 of the drawings. It will be understood that the spring 54 which normally maintains the arm 3 in raised posi- .-tion has less force than the spring 65 under against the work resting across the clincheru plates 18, it being understood that the clincher-plates are held in raised position by the step 25 on the slide 15 inserted beneath their lower edges, then the continued pressure on the knob 85 will slide the plunger 5 downwardly. As the plunger 5 is slid'downwardly on the head 4 the staple-driver 90 will descend against the 'foremost staple in the series which has been pushed off from the arm, 3,'see Fig. 2, it having been explained that the staples are fed into operative position by the staple-pusher 70 which is urged forward on the arm 3 by its spring 69. a It should here be noted that the plunger 5 is limited in its upward movement by the enga ement of the latch with the upper shoul er 117 on the'side-plates 57, these parts being in the position shown in Figs. 1 and 2. As the plunger descends the .catch of'the' latch 110 leaves the shoulder 117 and'passes down beyond the second shoulder118 as illustrated v in Fig. 5. Now, as the sliding movement of the plunger is continued the staple-driver 90 forces "the staple 8' down in the grooves 92 with' the. legs ofv the staplegstraddling the sides of the staple-su porter 95. -At' this point the staple is hel by the supporter 95 to prevent "itfrom dropping out, ofthe grooves 92 and in the. normal operation ofthe device as the stroke of.the-"Staple driVer, 90 is continued the staple will be orc'eddownwardly, into theJwork with the supporter,

swing ng back out of the-way as illustrated in Fig. 6.

As the 'staple'is" thusjdrien throug h the a work the continued downward descent. of the;

plunger 5 causes the tug 12(} on its side to 5 engage the toe 45 on the lever 42 to .rock the latter to draw the 3.7 forwardly, .Tlie

link 37 is thus caused to rock the connected lever 30 to slide the slide 15 rearwardly to withdraw its fingers or lugs 26 from in under the clincher-plates 18. This action allows the clincher-plates to slide downwardly under the continued pressure on the plunger 5 whereby the forward ends of the clinchers 22 are forced upwardly as they bear on the member 23. In this manner the grooved ends of the clinchers 22 are caused to engage the legs ofthe staple s to bend them over and force their points into the work in the inanner as illustrated in Fig. 4.

After the stapling operation has been completed and the legs of the staple clinched against the under side of the work as above explained the pressure on the knob is-released so that the plunger 5 will he slid upwardly under the action of its spring 65, thereby releasing the lever 42. When the plunger reaches the limit 'of its upward stroke the coiled spring 54 comes into action to raise the arm 3 into the position shown in Fig. 1 so that the finished work may be removed and the machine made ready for another stapling operation. As the arm 3 is ralsed it releases the clincher-plates 18 which are caused to slide upwardly under the pressure of the leaf-spring 46, the clinchers 22 thereupon dropping down into inoperative position as illustrated in Fig. 3. As soon as the clincher-plates 18 have been raised in this manner the slide 15 is slid forward under the action of its lever 30 operated from the spring 38 and the fingers or lugs 26 on the clincherrest 23 inserted under the lower edges of the clincher-plates to support them in position for the next stapling operation.

It will be understood that while the plunger 5 1S inits depressed relation the staples are prevented from feeding off from the end of the core or arm- 3 by the sta ple-driver 90, but as the driver is raised above the forward end of the arm the foremost staple in the series 1s fed into position to be acted upon at the next descent of the driver. plamed that when the plunger 5 is forced downwardly its trip-latch 110 moves therewith w1th its detent or catch 115 passing beyond the lower shoulder 118 on the side-plates 57 During this action the trip-latch slides wlth the plunger in the relation as illustrated in Fig. 5, but as the plunger reaches the extreme limit of its descent to cause the stapledriver to complete the stapling operation the catch 115 on the latch 110 is carried against the abutment or shoulder 119, see Fig. 5, whereby the latch is slid upwardly on the front of the plunger as shown in Fig. 6. Asthe latch 110-slides upwardly on the front of the plunger 5 its offset portion 114 cams against the upper edge of the slot 116 to-force the-toe'or catch 115 outwardly so that it may clear the lower shoulder 118 when the plunger is returned to first position; That is to It has been exsay, this camming action forces the catch 115 outwardly -to a sufficient extent to allow it to pass by the lower shoulder 118 so that the plunger makes its full stroke upwardly and is arrested by the engagement of the catch 115 with the upper shoulder 117.

It will now be explained how the latch 110 operates to prevent the full return of the plunger 5 when the stapling operation is not completed. Should the operator press the plunger 5 downwardly to such an extent as to carry the fed staple 8 down through the grooves 92 beyond the other staples in the series and then fail to complete the stroke of the plunger the staple being acted upon will be retained in the grooves by the staplesupporter but it is obvious that this staple will not be returned to first position to prevent a new staple being fed into the grooves.

The staple-driver 90 is therefore prevented from returning upwardly beyond the end of the core 01' arm 3 whereby to check the feed of the staples in the following manner. When the plunger 5 fails to complete its full stroke to engage the lower end of the latch 110 with the abutment or shoulder 119 the latch will -remain in the position illustrated in Fig. 5.

Therefore, as the plunger is slid upwardly again under the force of its spring the catch 115 on the latch will engage the lower shoulder 118 to prevent full return of the plunger so that thelower end of .the, staple-driver 90 is restrained from rising up above the end of the arm 3 and consequently it acts to hold the staples from feeding forward. In this waythe latch 110operates automatically to arrest the upward stroke of the staple-driver at a point where it functions to check the feed of the staples so that a new staple cannot be carried into driving position until the previously fed staple has been completely applied to the work. Through this improved means the machine is made proof against becoming clogged and also prevented from driving one staple on top of another or causing the staples to be bent or malformed as they are operated upon by the driver.

It will be observed from the foregoing that my invention provides a particularly simple and efficient machine for the purpose specified with its mechanism designed to resist wear and prevent derangement of the parts.

The arrangement of detachable side-plates 571 for the head 4 of the machine provides for the substitution of other plates having guideways or grooves .of different dimensions to accommodate staples constructed from different sizes of wire. For this purpose a different staple-driver is substituted and such changes may readily be made without disassembling the whole machine.

It has been stated that the staple-drivergralwith the ment of the machine; and it has also been noted that the clincher-rest or support may be ed from sheet-metal whereby to render them light in weight yet sturdy in construction and capable of being manufactured at low cost.

As another feature of'improvement the machine contains a minimum number of screws and rivets, certain of the parts being connected through means constructed intesheet metal stampings. Through these improvements the machine is rendered more eflicient and'durable in use and capable of beingmanufactured at low cost.

The present improved machine has been described as embodied in a preferred form of construction, but it is to be understood that various modifications may be made in the form and arrangement of the component parts of the device without departing from the spirit or scope of the invention.

Therefore, without limitation in this respect, I claim:

1. In a stapling machine, the combination of means for drivinga staple into the work, means for successively feeding staples to the driving-means, detent-means movable with the staple-driving means, means engageable with the detent-means for preventing the return of the driving-means to first position,

and a cam acting on the detent-means to shift it into inoperative position when the driving-means has been moved to the full extent to complete the operation of setting the stapie-in the work.

2. In a stapling machine, the combination of a reciprocable plunger, a staple-driver operated by the plunger, means for successively feeding staples to the driver, a latch movable with the plunger, a detent adapted to be engaged by the latch to hold the staple driver from returning to first position to prevent the feeding f the staples, and a cam rendered operative upon the completion of the stroke of the driver as the staple is driven into the work to throw the latch into inoperative position.

3. In a stapling machine, the combination of a stapling-head, a plunger reciprocable on said head, a staple-driver operated by the plunger, means for successively feeding staples to the driver, a detent on the head, a latch .on the plunger adapted to engage the detent-to hold the driver in position to prevent the feeding of the staples, and a cam.

acting to move the latch into inoperative position as the driver completes its stroke todrive the staple into the work.

v 4. In a stapling machine, the" combination of a reciprocable. 'staple-drivenmeans for tentnneans movable with the staple-driver, means engageable with the detent-means for restraining the driver against return movement to prevent'the feeding of a new staple until the previously fed staple has been driven into the work, and a cam rendered operative as the staple-driver reaches the end of its stroke to shift the detent-means into inoperative'position whereby to permit the staple-driver to return to first position.

5. In a stapling machine, the combination of a staple-driver, means for successively feeding staples to said driver, a detent-latch movable with the driver, a detent engageable with said latch to prevent the return of the driver to' first position, a cam on the latch, and 'means acting on the cam when the driver is moved to the full extent of its throw in completing the stapling operation to shift the latch into inoperative position to allow the driver to return to first position.

6. In a stapling machine, the combination of a reciprocable staple-driver, means for successively feeding staples to the driver,

means for returning the staple-driver to first position to act on a new staple after each stapling operation, a latch movable with the staple-driver and also movable longitudinally with respect thereto, a detent engageable with the latch to. prevent the stapledriver from returning to first position, and

means for moving the latch longitudinally with respect to the staple-driver as the latter reaches the end of its throw whereby to throw the latch into inoperative position with respect to the detent to permit the staple-driver to return to first position.

7. Ina stapling machine, the combination of a reciprocable plunger, a staple-driver reciprocated from said plunger, means for successively, feeding staples to the driver, a latch pivoted to rock on the plunger and also adapted to slide longitudinally with respect thereto, a detent adapted to be engaged by the latch to prevent the staple-driver from returning to first position, and means for sliding the latch on'the plunger to carry it into inoperative position with respect to the detent when the staple-plunger is moved to the full extent of its throw to drive the staple into the work. I

8. In a sta ling machine, the combination of a staplingead, a plunger reciprocable on said head,1a.-staple-driver reciprocated from said plunger, a'detent on the head, a latch pivoted to rock onthe plunger and also arranged to slide longitudinally w1th respect thereto, said latch formed with a cam-face, a" detent on the head adapted to be engaged by the latch to prevent the return of the plunger to first position, and means on the head engaging the latch to slide the latter to cause the cam to shift it into inoperative position with respect to the detent when the driver has been moved to the full extent to drive the staple into the Work.

9. In a stapling machine, the combination of a stapling-head, a plunger reciprocable on said head, a staple-driver reciprocable from the plunger, a detent on the head, a latch slidable on the plunger and also movable laterally to engage the detent on the head, said latch formed with a cam-face, means on the plunger engageable with said cam-face to remove the latch from operative position with respect to the detent on the head, and means for sliding the latch when the plunger is moved to the full extent of its throw in driving the staple into the Work whereby to cam it out of operative position to permit the plunger and staple-driver to return to first position.

10. In a stapling machine, the combination of a stapling-head having a detent-shoulder, a plunger slidable on the head to drive the staples into the work, means for returning the plunger to first position after it has been operated to drive a staple into the work, a latch on the plunger adapted to engage the detentshoulder to prevent the" full return of the plunger, camming-means for throwing the latch out of operative position, and means for actuating the camming-means when the plunger has been reciprocated to the full extent of its throw to drive a staple into the Work.

11. In a device of the type specified, the combination of a stapling-head having a plurality of detent-shoulders, a plunger slidable on the head, a staple-driver reciprocated from said plunger, means for returning the plunger to first position after it has been'operated to drive a staple into the work, a latch on the plunger adapted to engage one of the shoulders on the head to prevent the full return of the driver, and means operated when the plunger is reciprocated to the full extent of its throw to carry the latch into position to clear the first detent-shoulder but to engage with the second'shoulder to limit the return movement of the plunger.

12. Ina device of the type specified, the combination of a stapling-head having stepped detent-shoulde'rs at its upper end and an abutment therebelow, a plunger reciprocable on the head, a staple-driver operated from the plunger to drive the staples into the work, and a latch slidable on the plunger and provided with a catch adapted to engage the detent-shoulders on the head, said latch formed with a cam portion whereby when it is en-. gaged by the lower abutment it is moved thereby to cam the catch into position to clear one stepped shoulder while allowing it to engage the other shoulder.

13. In a device of the type specified, the combination of a stapling-head having stepped detent-shoulders at its upper end and an abutment therebelow, a hollow plunger reciprocable on the head and provided with a plurality of slots in its forward wall, a stapledriver operated from the plunger to drive the staples into the ,work, a latch having means at its upper end hooked through the upper slot in the plunger and its lower end offset to form a cam-face and provided with a detentcatch projecting through the lower slot in the plunger, and means for normally holding the latch in position to cause its catch to engage the lower detent-shoulder on the head while adapting the latch to be slid to engage its camface with the edge of the lower slot whereby to rock the'latch to cause its catch to clear the lower shoulder and engage with. the upper shoulder in the manner and for the purpose substantially as described.

14. In a device of' the type specified, the combination of a stapling-arm along which the staples are adapted to be fed, side-plates removably attached to the sides of the arm and provided with inner horizontal channels and vertical guideways for the staples, liningplates abutting the inner sides of the sideplates with their lower edges spaced above the top of the arm, a staple-driver slidable in the guideways of the plates, and means for reciprocating the driver-to cause it to act on the staples as they are delivered thereto to drive them into the work. p

15. In a device of the type specified, the combination of a stapling-arm for holding a supply of staples, a stapling-head comprising opposite side-plates secured to the sides of the arm and provided with guideways for the staples on their inner faces and guidinggrooves on their outer faces, a hollow plungerhaving its sides straddling the outer faces of the side-plates and formed with splines engaging the guidingrooves therein, and a staple-driver slidable in the guideways on the inner faces of the plates and connected to the plunger to be reciprocated therefrom.

16. In a stapling machine, the combination of a base, an arm hinged to said base, a stapling-head on said arm, a plunger reciprocable on the head, a staple-driver operated from said plunger to drive the staples into the Work, clincher-devices on the base adapted to be actuated to bend over and clinch the legs of the staple against the under side of the work, a lever on the base for controlling the operation of the clincher-devices, and a second lever on the head connected to operate the first lever and adapted to be actuated from the plunger at the end of its descent in driving a staple through the work.

combination of a base, clincher-devices at the the staples throu h the work, a lever on said head adapted to e rocked by the descent of the plunger, a second lever on the base connected to be rocked from the first lever, clincher-devices at the forward end of the base, and a slide operated from the second lever to control the action of the clincher-devices to render them operative to clinch the staples against the under side of the work.

18. In a device of the type specified, the combination of a base, vertically slidable clincher-plates at the forward end of the base, clinchers pivoted to said plates to adapt them to be operated by the sliding movement thereof, a slide in the base engaging beneath the clincher-plates to prevent their sliding movement, a lever for sliding the slide to release the clincher-plates, a spring for normally holding the slide in position beneath the plates, a stapling-arm hinged to the base, a plunger slidable at the forward end of the arm, a staple-driver operated from said plunger to drive the staples through the work a second lever adapted to be operated from sai plunger at the end of its descent in driving a staple throughthe work, and means connecting the second lever to operate the first lever to cause it to -retract the slide to allow movement of the clincher-plates to actuate the 80 clinchers.

19. In a device of the type specified, the

K combination of a hollow base provided with a vertical guideway at its forward end and having its upper Wall slitted to provide a strip formed mto a loop, a clincher-plate slidable in the guideway in the base and provided with a lateral slot, clinchers pivoted on the clincher-plate, a leaf-sprin held under the loop against the top'of the ase with its free end engaging the slot in the clincher plate to maintain the latter in raised position, a fixed support for the ends of the clinchers, means for normally reventing the clincherplate from sliding own in its guid'eway, a

stapling-head, a staple-driver reclprocable on the head to drive the staples into the work, a plunger forhperating the driver, and means operated from the lunger to release the clincher-plate where y the latter may be moved downwardly against the action of its spring to cause the clinchers to act to clinch the legs of the staple against the under side ofItlllie work. h fli testimony w ereof I a x m si ature.

lmiiw.

, ARTHUR H. MA 

